In an optical communication network for transferring high capacity information in Wavelength Division Multiplexing (WDM) mode, N optical signals with different wavelengths are multiplexed and concurrently transmitted through one strand of an optical fiber. The C-band wavelength region (1530 nm to 1565 nm) and the L-band wavelength region (1570 nm to 1605 nm) are principally used in the optical signals transmitted through the optical fiber, in which the transmission characteristic of optical signals is good. Meanwhile, for the purpose of wide-band/large-capacity transmission in an optical communication network of the WDM mode, researches have been vigorously made in order to use the O-band wavelength region (1285 nm to 1330 nm) and the S-band wavelength region (1460 nm to 1530 nm).
U.S. Pat. No. 7,003,205 issued on Feb. 21, 2006 discloses a wide-band dispersion controlled optical fiber. The optical fiber enables the use of optical signals in various wavelength regions in a wavelength division multiplexing mode communication network by controlling the position of the zero dispersion wavelength, and enables long distance transmission by controlling dispersion slope and bending loss. Furthermore, there is an advantage in that the optical fiber enables not only short distance transmission but also middle/long distance transmission using a single type of optical fiber because the optical fiber is controlled to have negative dispersion values in the O-band wavelength region and positive dispersion values with small deviations in the C-band and L-band wavelength regions.
When compared to the time-division multiplexing communication mode, the wave-division multiplexing communication mode is advantageous in that transmission capacity is greatly increased at small expense. Due to such an advantage, the wave-division multiplexing mode has been continuously developed for optical communication networks. However, the focus of prior art wave-division multiplexing transmission has been in the C-band and L-band.
Thus, what is needed is a method of extending wave-division multiplexed transmission into the O-band.